1332748-29-4

Upstream product

• 100-39-0 benzyl bromide 
• 4238-71-5 1-benzylimidazole 
• 39684-80-5 2-(tert-butoxycarbonylamino)ethyl bromide 
• 24424-99-5 di-tert-butyl dicarbonate 
• 558441-67-1 (2-imidazol-1-yl-ethyl)-carbamic acid tert-butyl ester 

Relevant academic research and scientific papers

DERIVATIVES OF IMIDAZOLE AND BENZIMIDAZOLE, METHOD OF PREPARATION AND USE THEREOF

The present invention provides derivatives of imidazole and benzimidazole based thiones and selones used for degrading various toxic heavy metal and salts thereof to a less toxic, stable and insoluble form. The present invention also provides the process of preparation of the said derivatives of imidazole and benzimidazole based thiones and selones and method of detoxification and degradation of various heavy metals including mercury in particular organomercurials, lead, arsenic, cadmium, copper and salts thereof using the said imidazole and benzimidazole-based thione and selone derivatives. The said derivatives have better degradation activity under physiologically and environmentally relevant conditions as well as greater acceptability in a wide range of bases.

N-heterocyclic carbene-amide rhodium(I) complexes: Structures, dynamics, and catalysis

The amide-functionalized imidazolium salts [BocNHCH2CH 2ImR]X (R = Me, X = I, 1a; R = benzyl, X = Br, 1b; R = trityl, X = Cl, 1c) bearing increasingly bulky N-alkyl substituents were prepared in high yields by direct alkylation of the (2-imidazol-1-yl-ethyl)carbamic acid tert-butyl ester; 1c is a crystalline solid also characterized by X-ray diffraction. These salts are precursors for the synthesis of rhodium(I) complexes [Rh(NBD)X(NHC)] (NHC = 1-(2-NHBoc-ethyl)-3-R-imidazolin-2-ylidene; X = Cl, R = Me (3a), R = benzyl (3b), R = trityl (3c); X = I, R = Me (4a)). All the complexes display restricted rotation about the metal-carbene bond; however, while the rotation barriers calculated for 3a,b and 4a matched the experimental values, unexpectedly this was not true in the case of 3c, where the experimental value was equal to that obtained for compound 3b (58.6 kJ mol-1) and much smaller with respect to the calculated one (100.0 kJ mol-1). The catalytic activity of the neutral rhodium(I) complexes 3a-c in the hydrosilylation of terminal alkynes with HSiMe2Ph has been investigated with PhC≡CH, TolC≡CH, nBuC≡CH, Et 3SiC≡CH, and (CPh2OH)C≡CH as substrates. The steric hindrance on the N-heterocyclic ligand and on the alkyne substrates affects conversion and selectivity: for the former the best results were achieved employing the less encumbered 3a catalyst with TolC≡CH, whereas by employing hindered alkynes such as Et3SiC≡CH or (CPh 2OH)C≡CH the hydrosilylation leads only to the formation of the β-(E)-vinylsilane and α-bis(silyl)alkene isomers. The complexes 3a,b have also been employed in the addition of arylaldehydes with phenylboronic acid, and like in the hydrosylylation case, the best results were obtained using 3a in the presence of aldehydes bearing electron-withdrawing groups, such as 4-cyanobenzaldehyde and 4-acetylbenzaldehyde as substrates.